/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.myfaces.jtracc.renderkit.html.util;




/**
 * Converts characters outside of latin-1 set in a string to numeric character references.
 * 
 */
public abstract class UnicodeEncoder
{
	/**
	 * Encodes the given string, so that it can be used within a html page.
	 * @param string the string to convert
	 */
	public static String encode (String string)
	{
		if (string == null)
		{
			return "";
		}

		StringBuffer sb = null;
		char c;
		for (int i = 0; i < string.length (); ++i)
		{
			c = string.charAt(i);
			if (((int)c) >= 0x80)
			{
				if( sb == null ){
					sb = new StringBuffer( string.length()+4 );
					sb.append( string.substring(0,i) );
				}
				//encode all non basic latin characters
				sb.append("&#" + ((int)c) + ";");
			}
			else if( sb != null )
			{
				sb.append(c);
			}
		}

		return sb != null ? sb.toString() : string;
	}


}
